This train carrying crude oil, igniting, erupting in flames, forcing homes to evacuate. One person reported dead. Fireball lighting up the sky. The fire still raging, center of the town destroyed. All of this happened just north of the border from maine in canada. Firefighters from both countries rushing to help and gio benitez is on the scene tonight. Reporter: David, firefighters describe this as a war zone. The train exploding overnight, virtually wiping out an entire downtown area. The freight train carrying 70 tankers of flammable crude oil through quebec derailed, around 1:00 a.M. This morning, sparking explosions and inferno seen from several miles away. We haven't gone down to take a look. We don't know the mechanism of the derailment. Reporter: At least 1,000 residents evacuated before flames consumed the town of lac-megantic. Car after car of the 73-car train exploded, spreading flames to homes in this hamlet of 6,000 but an unknown number of people are yet accounted for. The plane traveling flew quebec and heading into maine. A fleet of firefighters from maine, 135 miles south deployed to battle the blazes. Among concerns tonight it appears near the explosion site a bar was packed with people. No word on whether those people are alive. Your concern about those people who are missing? Absolutely. We can't get in there at this point. It's too early to tell. Reporter: You can't get in there? A large perimeter and the heat from the fire is preventing us from getting close in so we'll have to wait for the firemen to finish their work before we can get in there. Reporter: Our canadian partners at ctv are the train somehow became unlatched after the conductor had already left the train for the night. And as for that train, it was unmanned, officials haven't been able to recover much of the crude oil and that's because much of it has leaked into the water here, david.

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